n. the regions to the north of the Arctic Circle centered on the North Pole
n. a waterproof overshoe that protects shoes from water or snow
s. extremely cold
a. 北极的, 极寒的
n. 北极圈, 北极
1. The Arctic is home to many unique animals, such as polar bears.
北极是许多独特动物的家，比如北极熊。
2. Scientists study the Arctic to understand climate change better.
科学家研究北极以更好地了解气候变化。
3. The Arctic region is covered in ice for most of the year.
北极地区大部分时间都被冰覆盖。